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From Bryan Talbot <btal...@aeriagames.com>
Subject Re: hadoop consistency level
Date Thu, 18 Oct 2012 20:58:21 GMT
I believe that reading with CL.ONE will still cause read repair to be run
(in the background) 'read_repair_chance' of the time.

-Bryan


On Thu, Oct 18, 2012 at 1:52 PM, Andrey Ilinykh <ailinykh@gmail.com> wrote:

> On Thu, Oct 18, 2012 at 1:34 PM, Michael Kjellman
> <mkjellman@barracuda.com> wrote:
> > Not sure I understand your question (if there is one..)
> >
> > You are more than welcome to do CL ONE and assuming you have hadoop nodes
> > in the right places on your ring things could work out very nicely. If
> you
> > need to guarantee that you have all the data in your job then you'll need
> > to use QUORUM.
> >
> > If you don't specify a CL in your job config it will default to ONE (at
> > least that's what my read of the ConfigHelper source for 1.1.6 shows)
> >
> I have two questions.
> 1. I can benefit from data locality (and Hadoop) only with CL ONE. Is
> it correct?
> 2. With CL QUORUM cassandra reads data from all replicas. In this case
> Hadoop doesn't give me any  benefits. Application running outside the
> cluster has the same performance. Is it correct?
>
> Thank you,
>   Andrey
>

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